the old air assist question again (sorry)

[Margaret Turco]

Hi all,

I wanted to go ahead and buy a compressor for the air assist on my Universal V-460 which is supposed to be delivered on Monday.:D I will primarily be doing vector cutting so I know I need one, but don't want more than I need.

From reading all the many previous posts I could find here it appears that that others may be using a Harbor Freight 93657. I actually went and looked at this compressor and it looks inadequate. I also looked online at the 34843 model that another poster mentioned, but my local HF didn't stock that one. It only specifies 2 cfm @ 30 psi.

I also stopped at Sears to look at them in person and the salesperson tried to sell me a $400 35 gallon with 10.5 cfm. Overkill to say the least.

Could any of you verify that you use one of the two Harbor Freight models with a Universal laser? Otherwise, there are a few cheap ones on Craigslist I might as well check out. I have to go cut a hole in the wall for the exhaust now; wish me luck!

[Scott Shepherd]

Margaret, I can't speak for that model, but the current models require 2.5CFM at 40 PSI as a requirement. An airbrush compressor puts out more like .8 or .9 CFM at 30-40PSI.

If noise isn't a problem, go with the larger one with the tank and you'll be fine. If noise is a problem, then you're in trouble. You can't get those spec's with the words inexpensive inserted anywhere in the conversation.

One thing that's critically important is dry air. Make sure you have a way to dry the air. A drop of water into the mirror air shields or into the lens assembly and you'll be spending thousands to replace the mirrors and lens.

[Mike Null]

It is rare that I use my air assist at full pressure. I would guess that the HF unit would suffice and only costs about 15% as much as Gast units. There are quite a number of engravers using the HF units and I've not seen any comlaints. (I have 2 Gast units.)

I cut very little acrylic thicker than 1/8" so I don't need full pressure.

With the units such as Sears consider noise. They are extremely noisy. I use mine for my heat press as well as others tools in the shop.

[Bill Cunningham]

I have a 60 gal, tank on a 11 cfm machine in my shop.. I don't have it on full auto, I just top it up in the morning to 135 psi, and when it cuts out, I then turn off the switch. I regulate the shop line pressure to 80 psig, and have another regulator at the laser to take it down to about 25psig. It will supply air to the laser at a constant 25psi for several hours.. When it gets to about 75 psi (usually late in the day) I just flip on the switch and let her run until it reaches the cut out pressure again and shuts down.. Silent air, pretty well all day long (except for the two top ups), and it will still run all my air tools, and sandblaster when I need them...

[Margaret Turco]

Thanks Bill. I have some space issues although I may go that route in the future. I have a garage full of inherited shop stuff moved over to one side to make room for the laser. Looks like for now I'm going to use a little Husky like Joe has. My laser delivery is tomorrow and all day I've been thinking of other things I need. I really don't like shopping although the lady who helped me to some practice material at Lowe's was awfully nice, so that made the day a lot better. Along with you guys, of course!